This invention relates generally to an electronic timepiece and more particularly to an electronic timepiece comprising a fundamental frequency oscillator which feeds a plurality of frequency divider stages. Ideally in an electronic timepiece the fundamental frequency oscillator will put out an exactly predetermined frequency of signals. In conjunction with this precise frequency output, the divider would have a precisely determined number of stages to produce a lower frequency of the exactly desired rate suited to drive a timekeeping mechanism. Unfortunately, it is rarely possible to get the exact frequency from the oscillator which is desired. Accordingly, it is necessary to be able to determine the actual frequency output of a timepiece and to provide means for adjusting the timing rate from that timepiece to bring the accuracy of timekeeping within acceptable limits. In the prior art this has frequently been down by providing a trimmer capacitor in the oscillator circuit. However, there are several drawbacks to this technique for adjusting oscillator frequency. Generally speaking, the trimmer capacitor is most successful when the adjustment is to be made over only a narrow range of frequency. When the frequency is to be adjusted over a wide range of frequencies, the oscillations tend to become unstable. Also, the oscillation starting voltage becomes high. Further, when using the trimmer capacitor precise adjustment is a delicate procedure and the results are unstable. As a result, the adjustment of the timing rate is a time consuming procedure. Further, a trimmer capacitor is an expensive component and occupies a considerable volume of space in the timepiece.
What is needed is an electronic timepiece which can be adjusted to a highly accurate timing rate without the need for a trimmer capacitor. Also, it is desirable that these frequency adjustments can be made simply and rapidly and without the need to open the timepiece.